Add support for Websocket protocols.

tests/standalone/io/socket_test.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 // VMOptions=
 // VMOptions=--short_socket_read
 // VMOptions=--short_socket_write
 // VMOptions=--short_socket_read --short_socket_write
 
 import "dart:async";
@@ skipping 192 matching lines @@
               subscription.cancel();
               socket.close();
               server.close();
               asyncEnd();
             },
             onDone: () { Expect.fail("Unexpected pipe completion"); });
     });
   });
 }
 
+void testCloseWriteNoListen() {
+  asyncStart();
+  ServerSocket.bind(InternetAddress.LOOPBACK_IP_V4, 0).then((server) {
+    server.listen(
+        (client) {
+          client.close();
+        });
+    Socket.connect("127.0.0.1", server.port).then((socket) {
+      socket.close();
+      server.close();
+      asyncEnd();
+    });
+  });
+}
+
 main() {
-  asyncStart();
   testArguments();
   testSimpleBind();
   testInvalidBind();
   testConnectNoDestroy();
   testConnectImmediateDestroy();
   testConnectConsumerClose();
   testConnectConsumerWriteClose();
   testConnectStreamClose();
   testConnectStreamDataClose(true);
   testConnectStreamDataClose(false);
   testConnectStreamDataCloseCancel(true);
   testConnectStreamDataCloseCancel(false);
-  asyncEnd();
+  testCloseWriteNoListen();
 }